How to Know When You Have the Wrong Weed Eater Fuel Mixture?

Proper gas to oil ratio is essential to piston lubrication.

Putting the proper gas to oil mixture in your weed eater is essential in keeping the piston lubricated. Too much oil will not cause as much damage as too little. In fact, a little extra oil in the mixture will not cause any problems, but an excessive amount will be noticeable and should be corrected. Too little oil will scar the piston and no oil at all will cause the engine to seize within minutes of starting the unit and will cost more to repair than to replace the unit.

1

Put on ear and eye protection. Start the the weed eater and let it run at idle speed to warm up.

2

Press the throttle and observe the weed eater’s engine. If you see blue smoke coming out of the exhaust or oil dripping from the exhaust, the fuel ratio is too rich, meaning it has too much oil. Turn off the weed eater and replace the fuel with a properly mixed ratio of gas to oil.

3

Press down on the throttle and listen for a loss of power. Touch the outer part of the engine to see if it is hot. Notice if it smells hot, like metal rubbing against metal. If you notice either of these, the fuel mixture is too lean, meaning there is not enough oil mixed in with the fuel. Too little oil will damage an engine much quicker than too much oil. Stop the engine immediately and replace the fuel with a properly mixed ratio.

Things You Will Need

Eye protection

Ear protection

Gas container

Two-cycle oil

Fresh gasoline

Tips

Gently shake the container of oil and gas mixture before each use to ensure it is mixed thoroughly. This will eliminate separation and ensure you are getting the proper mixture in the trimmer.

Two-cycle oil is sold in a 2.6 ounce size making it easy to add it to 1 gallon of gas to obtain a 50:1 ratio. Add a 3.2 ounce size to 1 gallon of gas to obtain a 40:1 ratio.

Newer two-cycle engines are being manufactured to run cleaner. They use a gas to oil ratio of 50:1 where older units use a 40:1 or 32:1 ratio. Check the operator’s manual to find the ratio for your unit.

Warnings

Using straight gasoline will cause the engine to seize within minutes.

Use a two-cycle oil made for an air cooled engine, as some two-cycle oils are for water-cooled engines. Never use automotive oil in a weed eater.

Using gasoline more than six months old will cause loss of power in your weed eater.

Do not dump gas or oil on the ground. It will seep into groundwater or run into nearby storm drains contaminating groundwater and nearby bodies of water. Always recycle a gas and oil mixture at your local hazard waste facility.

About the Author

Diana K. Williams is a certified Master Gardener, has more than a decade of experience as an environmental scientist, and holds a Bachelor of Science degree in biology and environmental studies from the Ohio Northern University. Williams is a winner of Writer’s Digest Magazine's annual writing competition.